The San Diego Chargers have revamped every area for the upcoming season. Mike McCoy was brought in from Denver to replace Norv Turner as head coach, while Tom Telesco replaced general manager A.J. Smith. Dwight Freeney highlights the new additions to the roster, along with draft picks D.J. Fluker, Manti Teo and Keenan Allen.

There has been a plague for the Chargers this offseason and preseason: injuries.

The team also lost Melvin Ingram and Jonas Mouton for the season with torn ACLs, leaving the linebacker position with a lack of depth. Larry English, Bront Bird and Andrew Gachkar must step up this season for the Chargers.

Enough with the bad news; let's get focused on San Diego's first game against the Houston Texans.

Houston went 12-4 last season, improving its record by two games from the year before. Houston's definitely a top team in the AFC, with an elite running back, wide receiver and defense. The Texans defense is led by defensive end J.J. Watt, who won the defensive player of the year award last season.

All in all, Week 1 will not be easy for the Bolts.

Let's take a look at some pivotal matchups for the Chargers against the Texans.

Hopkins was drafted by the Texans in the first round of the 2013 NFL draft out of Clemson. Hopkins was the second receiver drafted this year, behind Tavon Austin. Houston really likes his potential as a starting wideout opposite of Andre Johnson. Hopkins caught six passes for 74 yards and a touchdown in three games this preseason.

On the Chargers side, Shareece Wright has had an excellent offseason and preseason. His great coverage and intensity has resulted, unfortunately, in three receiver injuries, as stated above. Wright collided with both Danario Alexander and Malcom Floyd, injuring the two of them, and was covering Eddie Royal when he went down.

It's okay to be upset at him for what's happened this preseason, but let's be optimistic here. Maybe Shareece Wright is on the verge of a breakout year?

Remember, he was having a phenomenal camp and preseason last year before he was injured on the opening kickoff of the regular season.

Now that we know Eddie Royal is ok, we can say Shareece Wright might be the most dangerous defender in the NFL. (Coincidence. But crazy.)

Pay close attention to this match-up. Hopkins may not be the best receiver that Wright will face this season, but it will tell a lot of what's to come with not only him, but the entire Chargers' secondary. After Eric Weddle, I see Shareece Wright as the most important player in that secondary.

Antonio Gates (TE) vs. Brian Cushing/Joe Mays (ILB)

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Antonio Gates looks ready for a huge year.

Antonio Gates has made a living making linebackers look silly. His athleticism and sharp moves allow him to create space for Rivers to get him the ball.

The reason you need to watch this matchup is based on wide receiver injuries. Philip Rivers has not yet perfected his chemistry with most of the receivers, leaving Gates as his priority target. In the preseason, there were a few series where Rivers targeted only Gates and no receivers.

Antonio Gates Stats

YEAR

Games Played

Receptions

Yards

Touchdowns

2012

15

49

538

7

2011

13

64

778

7

2010

10

50

782

10

2009

16

79

1,157

8

http://www.nfl.com/player/antoniogates/2505299/careerstats

If the Texans choose to defend Antonio Gates with either Brian Cushing or Joe Mays, expect him to play very well.

In the best shape of his career and healthier than he's been in three year, Antonio Gates should be back to shredding defenses, even at the age of 33.

Entire Offensive Line vs. J.J. Watt (DE)

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There is nobody more scared than Philip Rivers for the Week 1 game. No one lineman can block J.J. Watt in the NFL. San Diego will be doubling him on almost every play to keep its quarterback from getting crushed. Watt is a downright animal and will be causing all sorts of problems for the Chargers offense.

Watch this matchup closely. It will tell what the season will be like for Philip Rivers and the Chargers offense.

If King Dunlap, Chad Rinehart, Nick Hardwick, Jeromey Clary and D.J. Fluker can keep Watt from recording a sack, San Diego may be able to surprise some people this season. Even if he only sacks Rivers once, it will be impressive.